本節講兩種Mybatis開發方法:
(1)基於傳統的Dao的開發方法
(2)基於Mapper代理的開發方法
【基於傳統的Dao的開發方法】
目錄結構**
lib下目錄
UserDao.java
package com.zxy.mybatis.dao;
import com.zxy.mybatis.po.User;
/**
* dao接口
* @author zxy
*
*/
public interface UserDao {
//根據id查詢用戶信息
public User findUserById(int id)throws Exception;
//添加用戶
public void addUser(User user)throws Exception;
//刪除用戶
public void deleteUser(int id)throws Exception;
}
UserDaoImpl.java
/**
* UserDao接口的實現類
*/
package com.zxy.mybatis.dao;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import com.zxy.mybatis.po.User;
public class UserDaoImpl implements UserDao {
//通過構造方法注入SqlSessionFactory
private SqlSessionFactory sqlSessionFactory;
public UserDaoImpl(SqlSessionFactory sqlSessionFactory){
this.sqlSessionFactory=sqlSessionFactory;
}
@Override
public User findUserById(int id) throws Exception {
//因爲sqlSession線程不安全,所以需要定義在方法中
SqlSession sqlSession=sqlSessionFactory.openSession();
User user=sqlSession.selectOne("test.findUserById", id);
//釋放資源
sqlSession.close();
return user;
}
@Override
public void addUser(User user) throws Exception {
SqlSession sqlSession=sqlSessionFactory.openSession();
sqlSession.insert("test.insertUser", user);
sqlSession.commit();
sqlSession.close();
}
@Override
public void deleteUser(int id) throws Exception {
SqlSession sqlSession=sqlSessionFactory.openSession();
sqlSession.delete("test.deleteUser", id);
sqlSession.commit();
sqlSession.close();
}
}
User.java
package com.zxy.mybatis.po;
import java.util.Date;
public class User {
private int id;
private String username;// 用戶姓名
private String sex;// 性別
private Date birthday;// 生日
private String address;// 地址
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getSex() {
return sex;
}
public void setSex(String sex) {
this.sex = sex;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
@Override
public String toString() {
return "User [id=" + id + ", username=" + username + ", sex=" + sex + ", birthday=" + birthday + ", address="
+ address + "]";
}
}
UserDaoImplTest.java
package com.zxy.mybatis.dao;
import static org.junit.Assert.*;
import java.io.InputStream;
import java.util.Date;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.junit.Before;
import org.junit.Test;
import com.zxy.mybatis.po.User;
public class UserDaoImplTest {
private SqlSessionFactory sqlSessionFactory;
@Before
public void setUp() throws Exception {
String resource="SqlMapConfig.xml";
InputStream inputStream=Resources.getResourceAsStream(resource);
sqlSessionFactory=new SqlSessionFactoryBuilder().build(inputStream);
}
@Test
public void testFindUserById() throws Exception {
UserDao userDao=new UserDaoImpl(sqlSessionFactory);
User user=userDao.findUserById(16);
System.out.println(user);
}
@Test
public void testAddUser() throws Exception {
UserDao userDao=new UserDaoImpl(sqlSessionFactory);
User user=new User();
user.setSex("1");
user.setBirthday(new Date());
user.setAddress("shanxi");
user.setUsername("wnaghua");
userDao.addUser(user);
}
@Test
public void testDeleteUser() throws Exception {
UserDao userDao=new UserDaoImpl(sqlSessionFactory);
userDao.deleteUser(29);
}
}
User.xml
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="test">
<!-- 根據id獲取用戶信息 -->
<select id="findUserById" parameterType="int" resultType="com.zxy.mybatis.po.User">
select * from user where id=#{id}
</select>
<!-- 根據用戶名模糊查詢用戶信息 -->
<select id="findUserByName" parameterType="java.lang.String" resultType="com.zxy.mybatis.po.User">
SELECT * FROM USER WHERE username LIKE '%${value}%'
</select>
<!-- 插入用戶 -->
<insert id="insertUser" parameterType="com.zxy.mybatis.po.User">
<selectKey keyProperty="id" order="AFTER" resultType="java.lang.Integer">
SELECT LAST_INSERT_ID()
</selectKey>
insert into user(username,sex,birthday,address) values(#{username},#{sex},#{birthday},#{address})
</insert>
<!-- 刪除用戶 -->
<delete id="deleteUser" parameterType="java.lang.Integer">
delete from user where id=#{id}
</delete>
<!-- 更新用戶 -->
<update id="updateUser" parameterType="com.zxy.mybatis.po.User">
update user set username=#{username},sex=#{sex},birthday=#{birthday},address=#{address} where id=#{id}
</update>
</mapper>
log4j.properties
# Global logging configuration
log4j.rootLogger=DEBUG, stdout
# Console output...
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%5p [%t] - %m%n
SqlMapConfig.xml
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
<!-- 和spring整合後 environments配置將廢除-->
<environments default="development">
<environment id="development">
<!-- 使用jdbc事務管理-->
<transactionManager type="JDBC" />
<!-- 數據庫連接池-->
<dataSource type="POOLED">
<property name="driver" value="com.mysql.jdbc.Driver" />
<property name="url" value="jdbc:mysql://localhost:3306/mybatis?characterEncoding=utf-8" />
<property name="username" value="root" />
<property name="password" value="123" />
</dataSource>
</environment>
</environments>
<!-- 加載配置文件 -->
<mappers>
<mapper resource="sqlmap/User.xml"/>
</mappers>
</configuration>
基於Mapper代理的開發方法
四點需要遵守的規則:
(1) 配置文件UserMapper.xml的配置文件的namesapce屬性要設置爲Mapper接口UserMapper.java的地址所在
(2) mapper.java接口中的方法名和mapper.xml中statement的id一致
(3) mapper.java接口中的方法輸入參數類型和mapper.xml中 statement的parameterType指定的類型一致。
(4) mapper.java接口中的方法返回值類型和mapper.xml中statement
的resultType指定的類型一致。
目錄結構
UserMapper.java
package com.zxy.mybatis.mapper;
import com.zxy.mybatis.po.User;
/**
* mapper接口
* @author zxy
*
*/
public interface UserMapper {
//根據id查詢用戶信息
public User findUserById(int id)throws Exception;
//添加用戶
public void insertUser(User user)throws Exception;
//刪除用戶
public void deleteUser(int id)throws Exception;
}
User.java
package com.zxy.mybatis.po;
import java.util.Date;
public class User {
private int id;
private String username;// 用戶姓名
private String sex;// 性別
private Date birthday;// 生日
private String address;// 地址
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getSex() {
return sex;
}
public void setSex(String sex) {
this.sex = sex;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
@Override
public String toString() {
return "User [id=" + id + ", username=" + username + ", sex=" + sex + ", birthday=" + birthday + ", address="
+ address + "]";
}
}
UserMapperTest.java(測試文件)
package com.zxy.mybatis.mapper;
import static org.junit.Assert.*;
import java.io.InputStream;
import java.util.Date;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.junit.Before;
import org.junit.Test;
import com.zxy.mybatis.po.User;
public class UserMapperTest {
private SqlSessionFactory sqlSessionFactory;
@Before
public void setUp() throws Exception {
String resource="SqlMapConfig.xml";
InputStream inputStream=Resources.getResourceAsStream(resource);
sqlSessionFactory=new SqlSessionFactoryBuilder().build(inputStream);
}
@Test
public void testFindUserById() throws Exception {
SqlSession sqlSession=sqlSessionFactory.openSession();
UserMapper usermapper=sqlSession.getMapper(UserMapper.class);
User user=usermapper.findUserById(1);
sqlSession.close();
System.out.println(user);
}
@Test
public void testInsertUser() throws Exception {
SqlSession sqlSession=sqlSessionFactory.openSession();
UserMapper usermapper=sqlSession.getMapper(UserMapper.class);
User user=new User();
user.setSex("1");
user.setBirthday(new Date());
user.setUsername("力量12");
user.setAddress("山陰縣ads");
usermapper.insertUser(user);
sqlSession.commit();
sqlSession.close();
}
@Test
public void testDeleteUser() throws Exception {
SqlSession sqlSession=sqlSessionFactory.openSession();
UserMapper usermapper=sqlSession.getMapper(UserMapper.class);
usermapper.deleteUser(34);
sqlSession.commit();
sqlSession.close();
}
}
UserMapper.xml(方法沒有完全實現)
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.zxy.mybatis.mapper.UserMapper">
<!-- 根據id獲取用戶信息 -->
<select id="findUserById" parameterType="int" resultType="com.zxy.mybatis.po.User">
select * from user where id=#{id}
</select>
<!-- 根據用戶名模糊查詢用戶信息 -->
<select id="findUserByName" parameterType="java.lang.String" resultType="com.zxy.mybatis.po.User">
SELECT * FROM USER WHERE username LIKE '%${value}%'
</select>
<!-- 插入用戶 -->
<insert id="insertUser" parameterType="com.zxy.mybatis.po.User">
<selectKey keyProperty="id" order="AFTER" resultType="java.lang.Integer">
SELECT LAST_INSERT_ID()
</selectKey>
insert into user(username,sex,birthday,address) values(#{username},#{sex},#{birthday},#{address})
</insert>
<!-- 刪除用戶 -->
<delete id="deleteUser" parameterType="java.lang.Integer">
delete from user where id=#{id}
</delete>
<!-- 更新用戶 -->
<update id="updateUser" parameterType="com.zxy.mybatis.po.User">
update user set username=#{username},sex=#{sex},birthday=#{birthday},address=#{address} where id=#{id}
</update>
</mapper>
log4j.properties
# Global logging configuration
log4j.rootLogger=DEBUG, stdout
# Console output...
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%5p [%t] - %m%n
SqlMapConfig.xml
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
<!-- 和spring整合後 environments配置將廢除-->
<environments default="development">
<environment id="development">
<!-- 使用jdbc事務管理-->
<transactionManager type="JDBC" />
<!-- 數據庫連接池-->
<dataSource type="POOLED">
<property name="driver" value="com.mysql.jdbc.Driver" />
<property name="url" value="jdbc:mysql://localhost:3306/mybatis?characterEncoding=utf-8" />
<property name="username" value="root" />
<property name="password" value="123" />
</dataSource>
</environment>
</environments>
<!-- 加載配置文件 -->
<mappers>
<mapper resource="mapper/UserMapper.xml"/>
</mappers>
</configuration>